Microsoft Takes on Spam with Exchange Server 2003 SP1

by Alex Woodie

Microsoft's new spam-blocking technology has found its way into Exchange Server 2003 with the release of Service Pack 1, the first major update to its messaging software since its debut, in October 2003. In addition to a number of other enhancements and fixes, Service Pack 1 adds to Exchange Server 2003 the Intelligent Message Filter content filtering technology that Microsoft developed and refined on hundreds of thousands of MSN Hotmail e-mail accounts.

Despite efforts such as the CAN-SPAM Act of 2003, unwanted commercial e-mail continues to waste more of people's time than ever before. According to a recent survey of Fortune 500 companies conducted by Nucleus Research, the average yearly spam intake in 2004 has doubled since 2003, to an average of 7,500 per year, which contributed to a total loss of productivity of 3.1 percent for this year, up from 1.4 percent last year. When it's all said and done, unwanted commercial e-mail this year will cost companies $1,900 per spam-saturated employee.

Current antispam techniques aren't working as well as they could, or even once did. Spam now accounts for more than 70 percent of all e-mails, according to e-mail security provider MessageLabs. And Nucleus says spam filters have managed to snag only one in five pieces of spam this year. That .200 batting average sounds even worse when you consider that spam filters averaged a 26 percent success rate last year.

Microsoft aims to combat this growing spam problem with its new Intelligent Message Filter heuristics-based content-filtering tool. IMF uses Microsoft's SmartScreen technology, which was used to track more than 500,000 e-mail characteristics, culled from hundreds of thousands of MSN Hotmail subscribers. Those subscribers participated in a project that classified e-mail as either spam or non-spam, and based on the characteristics and patterns of those e-mails, Microsoft thinks it has found a pretty accurate way to tell whether an e-mail is spam.

Based on the "spam confidence level," which the IMF tool gives to an e-mail message, and the filtration settings that a user puts in place, Exchange can do several things with a potential piece of spam, including deleting it, archiving it, or forwarding it to its final destination. If users are equipped with Microsoft Outlook 2003, they are able to cut down on the instance of false positives by overriding the spam-confidence-level setting on Exchange.

While spammers are adept at defeating antispam techniques, Microsoft claims its IMF tool will be harder for spammers to crack. The software giant says that all spam has certain identifiable traits that can be categorized, which is the basis for the "intelligence" in IMF. Considering the declining success rate of antispam techniques, we'll believe Microsoft's claims when we see proof that they work.

The IMF tool was previously only available to Microsoft customers who participated in the Software Assurance, but the add-on is now available to all Microsoft Exchange Server 2003 customers with Service Pack 1. Microsoft is also battling spam on other fronts. The Redmond, Washington, company announced at its recent TechEd conference that it has agreed to converge its specification for fighting e-mail address "spoofers," which it calls Caller ID for E-mail, with the vendor-neutral Sender Policy Framework specification. It also filed lawsuits against a group of spammers last week.

Other enhancements in Microsoft Exchange Server 2003 Service Pack 1 include an updated antivirus API, enhancements to the Recover Mailbox Data wizard, an improved RPC/HTTP topology, new language support for Outlook Web Access and Outlook Mobile Access, and better support for coexistence and migration, through enhanced Active Directory and Lotus Notes R6 connectors. There are also a number of new security fixes in Service Pack 1.

For more information on Exchange Server 2003 SP1, or to download the service pack, go to Microsoft's Web site.